Effect of adenosine on injury caused by ischemia and reperfusion in rats: functional and morphologic study

To study whether treatment with adenosine (ADO), an agonist of adenosine receptors, attenuates intestinal dysfunction caused by ischemia (I) and reperfusion (R), we treated rats with ADO (15 mg/kg or saline solution (SS) intravenously before 60 minutes occlusion of the superior mesenteric artery (I) and/or 120 minutes after its release (R). After I or I/R, isolated jejunal segments (2 cm) were mounted in an organ bath to study nerve-mediated contractions stimulated by electrical pulses or KCI with the use of a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Compared with the sham group, jejunal contractions were reduced in I+SS and IR+SS but similar after treatment with ADO (I+ADO and IR+ADO groups). We concluded that rat jejunal enteric nerves were damaged in I+SS and IR+SS but not in the I+ADO and IR+ADO groups. These results suggested that ADO attenuated intestinal dysfunction due to I and R.